Comment by PaulKeeble

Typically at the moment we talk about a price of about $15 a MWH for Wind and $14 for Solar (last year anyway). So around $0.15 p/KWH for the power to charge and discharge it. Assuming the wind/solar is only going for a third of the day that brings the average price up to about $.209 p/kwh when we take into account battery wear cost. That is definitely economically viable in a very large number of places in the world.

Incidentally the totals work out about the same on a home solar system, my battery is 0.09 p/kwh and the Solar output averages out to about 0.07p/kwh but get paid for export at 0.15 p/kwh.